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Cell Numbering, Which is #1?

Discussion in 'Gen 3 Prius Technical Discussion' started by glue, Apr 6, 2023.

  1. glue

    glue New Member

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    I've seen some discourse and would like to know, which cell is #1 in a 2010 Prius?

    Especially in accordance with the Dr. Prius app, I'm trying to find a specific module. Is #1 on the side of the fan, or the opposite?

    I also don't have the best terminology, so answering in layman's terms would be very appreciated.

    Thank you for any input!
     
  2. Tombukt2

    Tombukt2 Senior Member

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    I saw a diagram of this the other day and don't know where I filed it away at but it should be on the web all over the place I mean the Gen 3 battery is pretty much a well-known piece and everybody wants to work on it and play with it so. The guys will be a long shortly that mess with the battery all the time and they'll tell you the exact layout I never really pay much attention to that because when my battery's failing I either get one rebuilt by a shop with the proper equipment to do all the stuff to make it work or I get a new rack of modules. I think the last time I looked a module set was about 1440 US dollars New I think
     
  3. ChapmanF

    ChapmanF Senior Member

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    Several others have offered a rule for use with any generation Prius:

    I even joined in the chorus myself:

    But, weirdly, that contradicts what I had already looked up in the manual for Gen 1 and posted nine years ago:

    So maybe Gen 1 was different. Enough people keep saying it starts at the negative cable, probably that's right for later generations anyway.

    It might be one of those things that's safest to look up in the manual. Also never hurts to check if there are numbers stamped on the module carrier.

    The discrepancy bugs me. Was page HV-9 in the Gen 1 2001 edition manual mixed up? Did I misread it? I wonder if @Elektroingenieur has any light to shed.

    Toyota Service Information and Where To Find It | PriusChat
     
    #3 ChapmanF, Apr 7, 2023
    Last edited: Apr 7, 2023
  4. PriusCamper

    PriusCamper Senior Member

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    Yea... My post was before I knew that Gen3 and Prius C was different than I first thought. I finally figure it out/confirmed by looking up which wire was the negative terminal that comes out of the circuits and into the pack. Gen3 and Prius C makes that info less obvious than what you see when you quickly glance at it.
     
    #4 PriusCamper, Apr 7, 2023
    Last edited: Apr 7, 2023
  5. ChapmanF

    ChapmanF Senior Member

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    The thing that still bugs me is Gen 1 counting from the positive-cable end. Kind of messes up the whole "they all count from the negative cable" thing.
     
  6. PriusCamper

    PriusCamper Senior Member

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    Even when you know how it works you can still get fooled. For example Nexcell re-sleeved my 2-1/2 year old lithium cells in my prototype pack because they were flimsy 3D printed modules and the production plastic modules are much more durable. Catch is they numbered the modules for install in a gen3 pack and I was installing them in the configuration of a Gen2 pack and I didn't double check.

    So I got the whole pack mounted to 1/2 the chassis and the wire frame bolted down only to realize the special module for orange service disconnect was in location 5 instead of location 10 and I had to take the whole pack apart and start over on mounting it to the chassis, which meant the grocery store closed before my car could get there. It made me sad, but you gotta double check that stuff so you don't do it wrong. :)

    (Note: Nexcell pack only has terminals on one side, with exception of the one module that has terminals on both sides so the orange service disconnect works.)
     
    #6 PriusCamper, Apr 7, 2023
    Last edited: Apr 8, 2023
  7. ChapmanF

    ChapmanF Senior Member

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    * frame wire
     
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  8. douglasjre

    douglasjre Senior Member

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    Won't matter which is #1 because ur getting a whole new pack
     
  9. PriusCamper

    PriusCamper Senior Member

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    Yes "Wire Frame No. 2" is the part name, at least for Gen2, but "Voltage Sensor Assembly" (VSA) would probably be more accurate than "frame wire." Maybe we should do a poll? :)
     
  10. ChapmanF

    ChapmanF Senior Member

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    No, that is not the part name, and if it were, I would not have made that post.

    Take a look again in the part catalog. See the commas?

    2fw.png

    The commas tell you that the part name has been folded where the commas are to make it come out alphabetically with other different kinds of wires, and that the name of the part is "No. 2 Frame Wire".

    If you go around calling things "plug sparks" or "pump waters" because you see "plug, spark" or "pump, water" in catalog listings, then you'll probably also call the no. 2 frame wire the "wire frame no. 2". But otherwise, not so much.

    This may seem very minor to bother pointing out to people. But it turns out there are a lot of people who haven't quite learned how to read catalog names that are folded that way, and there was a recent thread just last month where two different expensive parts of the brake system got mixed up, not noticing a name was comma-folded in the parts catalog.

    It's important for people to know how to read those.
     
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  11. PriusCamper

    PriusCamper Senior Member

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    Let me guess... You aren't bilingual? Only speak one language? Extremist ideologies about punctuation and proper naming and posting at great length about typos is something that happens in the US where too many people only speak one language.

    Meanwhile in almost all of the rest of the world you need to know multiple languages just to function.

    And when you know multiple languages, not only are you less uptight about these kinds of things, but you're also more tolerant of people being different and accept that it's often not easy to make sense of what people say and what really matters is putting your energy into understanding them and furthering the conversation rather than correcting them and demanding they conform to their selfish expectations.
     
    #11 PriusCamper, Apr 8, 2023
    Last edited: Apr 8, 2023
  12. ChapmanF

    ChapmanF Senior Member

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    Edit: I had a different, longer response here, but then realized I had let what you wrote throw me off the actual issue, which is simpler.

    The shorter response is that this isn't a case at all of me telling anybody how something should be named or punctuated.

    It is a case where Toyota already named something, and when we look in the parts list we see their chosen name, the way they chose to write it, and the way they chose to punctuate it. So it's up to us to make sense of what they already wrote.

    That makes it a perfect opportunity for doing exactly what you write about here: using your finely-honed multilingual skills to to recognize the way they expressed themselves, and to put your energy into understanding what they wrote. If you don't spot that they wrote "no. 2 frame wire" in comma-folded form as "wire, frame, no. 2", and you come away thinking the part name was "wire frame no. 2", you haven't understood what they wrote.

    What makes that worth the time to point out in a PriusChat thread is that we often fall into thinking a thread is just a conversation between people involved at the time, when really it's a permanent record (nearly always, excepting the very few that get deleted). Future readers are always coming along to learn stuff from it. If there's a post that says "Yes 'Wire Frame No. 2' is the part name" as a result of not understanding what Toyota wrote, that misinforms unknown numbers of people over indefinite future time.

    What wouldn't be worth the time to point out would be just "the name isn't this, it's that." Yawn. But a pattern of people getting a name inside out because not everybody learns how to read comma-folded things in parts lists anymore, that's worth pointing out, because then people can say "oh! I get it, now I know how to read all these other names I see in the parts lists also."

    That's helping people pick up a useful skill. In cases like the one last month where the names being confused were of four-figure-priced brake parts, a skill like that could save somebody some dough.
     
    #12 ChapmanF, Apr 8, 2023
    Last edited: Apr 8, 2023
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  13. AzusaPrius

    AzusaPrius Senior Member

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    The #1 block is the fan side in 2010-2015

    So if you are looking into the trunk from outside then it is on your right.

    Why was this so hard to answer??
     
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  14. robinredd1

    robinredd1 Junior Member

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    but on a 2012 prius c looking in from outside hatch the fan to the hv battery is on the LEFT behind the drivers side. and the orange cable connects to one side of the hv pack to the negative battery relay and the opposite side the same orange cable connects to the negative module . so what negative side is module 1 start from ? thank you
     
  15. robinredd1

    robinredd1 Junior Member

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    did you ever find out
     
  16. TMR-JWAP

    TMR-JWAP Senior Member

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    On the ends of the battery pack, the module will have a heavy orange cable connected to one terminal. Whichever module has the orange cable connected to the (-) terminal should be #1
     
  17. ChapmanF

    ChapmanF Senior Member

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    There's a post over here that shows how you can double-check using the color codes of the voltage-sensing wires (the skinny ones that connect at every second module down the length of the pack).

    There's been a rule often given that "#1 is where the cable goes on the ⊖ end of the module", but the gen 1 Prius was an exception to that rule. Maybe the rule is right for all the generations after gen 1, but usually as soon as I see one exception to a "rule" I become cautious about it, and just say "eh, I'll double-check for my car".

    The post I linked doesn't include the diagram with color codes for Prius c, so somebody might have to look that up.

    Toyota Service Information and Where To Find It | PriusChat

    One case where the color coding might not be enough would be if there's been previous work on the battery and that voltage-sensing wire harness (or "no. 2 frame wire") was replaced with an aftermarket one; those might not match the factory color codes.

    In a car where the "connected at ⊖ end is #1" rule holds—remember it doesn't hold for all generations, but in a car where it does—the location that matters is where the cable connects to that module, not wherever the other end of the cable might attach to the relay.
     
    #17 ChapmanF, May 14, 2024
    Last edited: May 14, 2024